HDOJ 2011

#include "stdio.h"
#include "math.h"

int main(void){
	int num;
	
	while(scanf("%d", &num) != EOF){
		int i;
		
		for(i=0; i<num; i++){		//循环次数 
			int j;
			int number;
			double sum = 0;
			
			scanf("%d", &number);
			for(j=1; j<=number; j++){
				sum += 1.0/j * pow(-1,j+1);		
			}
			printf("%.2lf\n", sum);
		}
		
	}
	
	return 0;
}